Fig. 6. Specific repression of GLP in murine PGCs before their epigenetic reprogramming. (A) GLP expression (red, left) in PGCs (green, middle) in the extra-embryonic mesoderm at E7.75, and in the developing hindgut endoderm at E7.75 and E9.5 as indicated. (B) G9a expression (red, left) in PGCs (green, middle) in the developing hindgut endoderm at E7.75 (top) and at E9.5 (bottom). Images merged with Hoechst staining (blue) are shown on the right (A,B). (C) Triple staining of Blimp1-positive cells (green), GLP (red) and H3K9me2 (white), in addition to Hoechst (blue) at E7.5 (LB). Two representative fields are shown. Arrowheads indicate PGCs with repressed GLP but with high H3K9me2 (white), with high GLP with high H3K9me2 (pink), and with repressed GLP and reduced H3K9me2 (green). (D) Number and percentage (in parenthesis) of H3K9me2 weak-, GLP-negative and GLP-positive and H3K9me2 weak-cells among Blimp1-positive cells in two LB-stage embryos. Scale bars: 10 µm in A-C.